Novel nickel alcoholates and alcohols thereof and a process of their production

ABSTRACT

PROCESS OF PRODUCING NICKEL ALCOHOLATES BY REACTING $-ALLYL NICKEL COMPOUNDS WITH CARBONLY COMPOUNDS. THE NICKEL ALCOHOLATES SO PRODUCED CAN BE HYDROLYZED TO THEIR CORRESPONDING ALCOHOLS AND THESE ALCOHOLS CAN IN PART BE DEHYDRATED TO THEIR CORRESPONDING OLEFINS. THE NICKEL ALCOHOLATE PRODUCTS ARE USEFUL FOR THE PRODUCTION OF THEIR CORRESPONDING ALCOHOLS AND THESE ALCOHOLS ARE USEFUL FOR THE PRODUCTION OF THEIR CORRESPONDING OLEFINS.

3,832,371 NOVEL NICKEL ALCOHOLATES AND ALCOHOLS THEREOF AND A PROCESS OFTHEIR PRO- DUCTION Gunther Wilke and Paul Heimbach, Mulheim (Ruhr),Germany, assignors to Studiengesellschaft Kohle mbH., Mulheim (Ruhr),Germany No Drawing. Original application Oct. 26, 1967, Ser. No.678,172, now Patent No. 3,544,604. Divided and this application July 29,1970, Ser. No. 64,845 Claims priority, application Germany, May 26,1967, ST 26,928 Int. Cl. C07f 15/04 US. Cl. 260-439 R 6 Claims ABSTRACTOF THE DISCLOSURE Process of producing nickel alcoholates by reactingar-allyl nickel compounds with carbonyl compounds. The nickelalcoholates so produced can be hydrolyzed to their correspondingalcohols and these alcohols can in part be dehydrated to theircorresponding olefins. The nickel al coholate products are useful forthe production of their corresponding alcohols and these alcohols areuseful for the production of their corresponding olefins.

This application is a division of application No. 678,172, filed Oct.26, 1967, now Patent No. 3,544,604.

This invention relates to novel nickel alcoholates and alcohols thereofand to a process of preparing said novel nickel alcoholates andalcohols.

According to German Pat. 1,191,375, it is possible to prepare complexesof transition metals by reducing compounds of transition metals withorganometallic compounds of the metals of Groups I to III of thePeriodic Table in the presence of electron donors. This process permitsalso the preparation of complexes of zero-valent nickel such asall-trans-cyclododecatri 1,5,9 ene-nickelbis(cyclooctadi-1,5-ene)-nickel (0), cyclooctatetraene-nickel (0),tetrakis(triphenylphosphine)nickel (0).

In further developing this process, it has been found that, indisplacement reactions, the ligands bonded to the central metal may bereplaced by other ligands. For example,all-trans-cyclododecatri-1,5,9-ene-nickel (0) reacts at as low as about60 C. with butadiene. Thereby, the cyclododecatriene is displaced andthere is formed a C bis-1r-allyl system I bonded to nickel bycombination of three butadiene molecules each:

CDT -Ni 3C4Hu CDT=cyclododecatriene United States Patent 0 MGR-435E:200D C H H COD =cyclooctadiene After hydrolysis of the nickelate, thediol which may be converted in known manner into1,6-diphenylhexatri-1,3,5- ene is obtained in high yields.

The process according to the invention for the production of novelalcohols and nickel alcoholates thereof comprises (a) allowing carbonylcompounds and 1,3-diolefins to act on complexes of nickel (0) or (b)reacting 1r-allyl nickel compounds with carbonyl compounds, thenhydrolyzing the resultant novel nickel alcoholates in known manner and,if desired, dehydrating the alcohols.

Nickel alcoholates produced according to this invention have the formulawherein R is hydrogen, alkyl, alkenyl, alkinyl, alkyldiene, aralkyl,aralkenyl, aryl-substituted aryl, arylalkyldiene, cycloalkyl-substitutedcycloalkyl, alkoxyaryl and substituted alkyl, and R is hydrogen, alkyl,substituted alkyl, aryl and substituted aryl.

The process of the invention has been found to be generally applicable,i.e. both the carbonyl compounds and the 1,3-diolefins may be varied inany manner. Suitable carbonyl compounds which may be used includealiphatic, alicyclic, saturated and unsaturated aldehydes and ketonesand saturated and unsaturated aldehydes and ketones which aresubstituted by aromatic radicals. Examples include formaldehyde,acetaldehyde, proprionaldehyde, butryric aldehyde, acrolein,crotonaldehyde, hexadienal, propargyl aldehyde, benzaldehyde, cinnamicaldehyde, phenylpentadienal, vitamin A aldehyde, anisic aldehyde,vanillin, acetone, methyl ethyl ketone, mesityl oxide, cyclopentanone,cyclohexanone, acetaphenone, benzophenone, fi-ionone. Aliphatic,alicyclic staurated and unsaturated dialdehydes and diketones andsaturated and unsaturated dialdehydes and diketones which aresubstituted by aromatic residues may also be used. Examples includeglyoxal, malonic dialhehyde, succinic dialdehyde, diacetyl, acetylacetone, acetonyl acetone, benzil, benzoyl acetone. When usingdialdehydes and diketones, longer chains having recurring monomericunits may be formed. Suitable 1,3-diolefins are butadiene or butadieneswhich are substituted by aliphatic, alicyclic or aromatic radicals suchas isoprene, 2,3-dimethyl butadiene, 2,3-diphenyl butadiene. Both thecarbonyl compounds and the 1,3- diolefins may contain functional groupswhich, however, are groups which are not reactive or react very muchslower with the metal atoms than the carbonyl group or 1,3-diolefingrouping. Examples of such functional groups include ether, ester,acetyl, amine and nitrile' groupings.

The process of the invention may be advantageously carried out byallowing the carbonyl compounds and the 1,3-diolefins to act directly onthe isolated complex compounds of nickel. Another particularlyadvantageous method of carrying out the process is to reduce nickelcompounds such as nickel acetyl acetonate by means of organometalliccompounds in the simultaneous presence of carbonyl compounds and1,3-diolefins according to the process described in German Pat.1,191,375. The nickel atoms obtained during the reduction act then inthe same manner as the meal atoms combined in the isolated complexes.This embodiment just mentioned permits the use of catalytic amounts ofnickel in performing the reaction which normally proceedsstoichiometrically with respect to nickel because the nickelates beingproduced during the carbonyl compounds or the 1,3-diolefins themselvesmay also serve as solvents. The reaction is carried out at temperaturesof from 0 to 200 C. and preferably at to 100 C. The nickel alcoholatesmay either be isolated and subsequently subjected to hydrolysis ordirectly hydrolyzed without being isolated.

The alcohols obtained by hydrolysis of the nickel alcoholates obtainableby the process according to the invention are valuable startingmaterials for further syntheses, especially for the production ofpolyenes. Thus, when starting from vitamin A aldehyde, butadiene andnickel, the process according to the invention gives a nickel alcoholatewhich, when hydrolyzed, furnishes a diol the dehydration of which leadsto a 0 1-1 polyene which is a homologue of beta carotin.

CHO

l-NKOH):

process of the invention may in turn be reduced. The process remains astoichiometric reaction with respect to the organometallic componentused.

In this reaction according to the invention, ar-allyl nickel alcoholatesare formed:

According to the invention, products of this kind may be preparedadvantageously from bis-1r-allyl compounds of nickel and carbonylcompounds. In this manner, the C bis-vr-allyl compound mentioned abovereacts with, for example, benzaldehyde to form a 1r-allyl nickelalcoholate.

out in the presence of solvents such as aliphatic, alicyclic or aromatichydrocarbons, ethers or esters. However, the

EXAMPLE 1 9.3 Grams:33.8 mmoles of (COD) Ni are suspended in ml. ofether and reacted at -30 C. with a solu tion of 5.0 g.=113 mmoles ofacetaldehyde in ether. Then 3 g.=55.5 mmoles of butadiene are introducedand the reaction is allowed to proceed at 20 C. After 24 hours, themixture is filtered. A light violet, sparingly soluble precipitate isobtained. The solution is almost colorless. Yield: 6.4 grams==3l.8mmoles=94% of the theory.

C H O Ni: Calculated, 29.2% Ni; found, 30.1% Ni.

A portion of 3.6 g.=17.9 mmoles of the alcoholate are reacted with 100mol. of aqueous alcohol (5% of water). After 24 hours, the greensuspension is freed from the solvents at 10* mm. Hg. The green residueis extracted with ether, the extract is evaporated and the residuedistilled; b.p.=90.95 C./0.05 mm. Hg. Yield; 2.2 g. of a viscous oilwhich, according to analysis by gas chromatography, consists of 97% ofoctene-(4)-diol- (2.7). Yield, 83% of the theory.

EXAMPLE 2 Ni; M=325.01.

Grams=10.4 mmoles of 1,6-diphenyl-trans-hexene-(3)- diol-(1,6)=80% ofthe theory are obtained. Melting point, 117-118 C. afterrecrystallization from benzene/ petroleum ether.

C H O Calculated, 80.56% C; 7.51% H. Found, 80.21% C; 7.62% H.

5 Grams=18.6 mmoles of diphenyl hexenediol are dehydrated with 5 ml. ofPOCl in 30 ml. of anhydrous pyridine by the process of Greidinger andGrinsberg to give 2.6 g.=11.2 mmoles=60% of the theory of 1,6- diphenylhexatri-1,3,5-ene having a melting point of 200 C. afterrecrystallization from benzene/petroleum ether.

EXAMPLE 3 7.4 Grams=27 mmoles of (COD) Ni are suspended in 100 ml. ofbenzene. To the suspension are added dropwise 7.3 g.=55" mmoles ofcinnamic aldehyde while vigorously stirring. The brown precipitatedissolves completely upon introduction of 3 g.=55 mmoles of butadiene.Then 5.8 g.=58 mmoles of acetyl acetone are added and 7 g.=21.9mmoles=81% of the theory of 1,10-diphenyl decatri-1,5,9-ene-diol-(3.8)are isolated. Melting point, 125-127 C. after recrystallization frombenzene/petroleum ether.

C H O Calculated, 82.46% C; 7.59% H. Found, 82.29% C; 7.57% H.

Melting of 3 g. of diphenyl decatrienediol together with 1 g. of freshlyannealed potassium bisulfate at 120 C. and extraction of the residuewith a boiling mixture of methanol and benzene gives 1.87 g.=6.6mmoles=70% of the theory of 1,10-diphenyl decapentaene-(1,3,5,7,9)melting at 253 C.

EXAMPLE 4 When adding dropwise 16.3 g.=110 mmoles of phenyl pentadienalto the suspension of 14.3 g.-=52 mmoles of (COD) Ni in 100 ml. ofbenzene, a clear and deep red solution is intially formed. From thissolution, crystalline phenyl pentadienal-Ni.COD precipitates. Whenintroducing 7 g.=129 mmoles of butadiene, the precipitate dissolvesslowly with the color turning brown. After 24 hours of reaction, 11.6g.=116 mmoles of acetyl acetone are added dropwise and after further 24hours 7.7 g.=23.5 mmoles=45% of the theory of light yellow crystallne1,14-diphenyl tetradecapentaene-(1,3,7,11,13)-diol-(5,10) are isolated.

C H O Calculated 83.83% C; 7.59% H. Found, 83.39% C; 7.62% H.

1.0 Gram=3 mmoles of diphenyl tetradecapentaene diol are heated withfreshly annealed potassium bisulfate for 2 hours at 170 C. Thereafter,the mixture is thoroughly washed with hot water and repeatedly boiledwith benzene and chloroform. Upon cooling, 0.6 g.=2.4 mmoles=80% of thetheory of 1,14-diphenyl-tetradecaheptaene- (1,3,5,7,9,11,13)precipitate. Melting point, 277 C. after recrystallization fromchloroform.

EXAMPLE 5 A solution of 6.5 g.-=22.8 mmoles of vitamin A aldehyde inbenzene was added dropwise to 3.1 g.'=11.2-7 mmoles of (COD) Ni in 100ml. of benzene. 3.4 Grams=62.8 mmoles of butadiene are introduced intothe red soltuion. After a reaction time of 4 days, the solvents areremoved at mm. Hg, the brown residue suspended in 100 ml. of aqueousalcohol (5% Water) and the Ni(OH) removed. 7.3 Grams of C diol in theform of an orange oil are obtained as residue.

A solution of 7.3 g. of C diol in 70 ml. of boiling benzene is mixedwith 250 mg. of N-bromosuccinimide. After a few seconds, the yellowsolution turns dark red. At the same time, water condenses in the refluxcondenser. After further 3 minutes at 80 C., the mixture is cooled,diluted with 300 ml. of petroleum ether and successively washed withsolutions of potassium iodide, sodium thiosulfate and sodium chloride.Drying of the solution over sodium sulfate and concentration gi-ves 7.3

g. of an oil which is dissolved in 18 ml. of benzene/ ethanol while hot.At 0 C., 1.0 gram of C hydrocarbon precipitates which is repeatedlyrecrystallized from ben- Ilene/ethanol. Yield, 1.0 g. =1.7 mmoles of CI-I =15%, based on (COD) Ni charged. Melting point, 194-196 C.

EXAMPLE 6 A suspension of 11.9 g.=='43.4 mmoles of (COD) Ni in ml. ofacetone is prepared. Into the suspension, 6.0 g.=11 mmoles of butadieneare introduced at room temperature. Thereby, the yellow suspension turnsdark red. After stirring for two days, the color of the reaction mixtureturns green. At the same time, the contents of the flask solidify toform a gel. The volatile constituents are distilled off at 0.5 mm. Hg toleave 10.7 g. of a solid residue which is extracted in a Soxhlet for 48hours with 100 ml. of ether. The residue sublimes at 10- mm. Hg and 70C. There are obtained 4.5 g.=26 mmoles=60% (based on nickel charged) of2,7-dimethyloctene-(4)-diol- (2,7). Melting point, 85- 86 C.

'C H O Calculated, 69.72% C; 11.70% H; M: 172.20. Found, 69.72% C; 11.4%H; M=172.

When carrying out the reaction at 70 C. in a bomb tube, the sameconversion is obtained in about 5 hours. The results correspond to thoseof the preceding experiments.

EXAMPLE 7 11 Grams=20 mmoles of butadiene are introduced into asuspension of 19.55 g.=71 mmoles of (COD) Ni and ml. of cyclohexanone.After as little as about 4 hours, the color turns green. The greengel-like reaction mixture is diluted with 100 ml. of ether, shaken with50 ml. of 2N H 50 and washed with NaHCO until it is free from acid.After drying over anhydrous Na SO excess butadiene and the ether aredistilled off from the colorless solution. Recrystallization of theresidue remaining after distillation from benzcne/ petroleum ether gives11.6 g.= 46 mmoles=65% of the theory of colorless1,4-di(cyclohexanolyl-1)butene-(2) having a melting point of 101 C.

C H O Calculated, 76.14% C; 11.10% H. Found, 76.59% C; 11.02% H.

EXAMPLE 8 12.0 Grams=22 rnmoles of butadiene are introduced into asuspension of 20.4 g.=74 mmoles of (COD) Ni in 100 ml. of acetophenone.The (COD) Ni dissolves while the color turns red. After stirring forthree days at about 20 C., the gel-like reaction mixture which is nowgreen is diluted with 200 ml. of ether, washed with 50 ml. of 2N H 50neutralized with a NaHCO solution and dried over Na SO After severaldays, 3 grams of 1- methyl-(1,3,5)-triphenyl (2) benzoylcyclohexadiene-(2,4) precipitate from the yellow solution. Melting point, 136 C. afterrecrystallization from methanol.

C H O Calculated, 90.01% C; 6.14% H. Found,

89.89% C; 6.20% H. At 10 mm. Hg and about 20 C. butadiene, COD andacetophenone are removed as far as possible from the mother liquor.There remain still 395 grams from which a yellow liquid can be distilledoff at 10' mm. Hg and a bath temperature of 140-150 C., this liquidconsisting of 89% of dypnone.

From the residue remaining at C., 14 g.=63% of the theory of2,7-diphenyl-octene-(4)-diol-(2,7) are obtained. Melting point, 114 C.after recrystallization from benzene petroleum ether.

C H O Calculated, 81.04% C; 8.16% H. Found, 81.22% C; 8.02% H.

EXAMPLE 9 6.8 Grams=100 mmoles of isoprene are added drop- Wise at 20 C.to a suspension of 11.6 g.=42 mmoles of (COD) Ni in 52 g.=49.3 mmoles ofbenzaldehyde and 50 ml. of alcohol (5% of water) while stiring. Thereaction begins instantaneously and the temperature rises to about 40 C.with the mixture becoming solid like a gel. There are obtained 7.5g.=26.6 mmoles=63% of the theory of1,6-diphenyl-(3)-methyl-hexene-(3)-diol-(1,6) having a melting point of125l26 C.

C H O Calculated, 80.81% C; 7.81% H. Found: 81.08% C; 7.98% H.

EXAMPLE 10 8.8 Grams=l07 mmoles of 2,3-dimethyl butadiene are addeddropwise to a mixture of 13.1 g.=47 mmoles of (COD) Ni in 52 g.=493mmoles of benzaldehyde and 50 m1. of alcohol (5% of water). The colorchange occurs after 3 hours. After further 24 hours, 6.9 g.=23.3mmoles=50% of the theory of 1,6 diphenyl (3,4)- dimethylhexene-(3)-diol(1,6) having a melting point of 129l30 C. are obtained.

C I-I O Calculated, 81.04% C; 8.16% H. Found: 81.41% C; 8.19% H.

EXAMPLE 1 1 A solution of 1.1 g.=10 mmoles of benzaldehyde and 1.0 g.=46mmoles of 2,3-diphenyl butadiene in 10 ml. of benzene is added dropwiseto a suspension of 1.0 g.=36 mmoles of (COD) Ni in 30 ml. of benzene.After 24 hours, 1.0 g.=10 mmoles of acetyl acetone is added to the darkred solution whereupon the color of the solution turns green throughbrown. 0.7 Grams=l.7 mmoles=47% of the theory ofl,3,4.6-tetraphenylhexene- (3)-diol-(l,6) having a melting point of134135 C. could be isolated.

C H O Calculated, 85.67% C; 6.71% H. Found: 85.65% C; 6.88% H.

EXAMPLE 12 A solution of 3.3 g.=23.4 mmoles of bis(1r-allyl) nickel in100 ml. of ether is reacted at C. with 2.5 g.=23.5 mmoles ofbenzaldehyde. The mixture turns dark red. After 12 hours, the volatileconstituents are removed at 10 mm. Hg. The residue weighing 5.1 g. isdissolved in 40 ml. of pentane and recrystallized at 80 C. Yield: 3.5-g.=l4.1 mmoles of 1r-allyl-nickel-l-phenylbutene-(3)- olate=60% of thetheoretical yield.

C H ONi: Calculated, 23.8% Ni; M=246.5. Found, 24.1% Ni; M=498.

3.5 Grams=14.1 mmoles of the alcoholate are reacted with 100 ml. ofalcohol (5% of water). After 24 hours, the green suspension is freedfrom the solvents at mm. Hg. The green residue is extracted with etherand the extract evaporated. There are obtained 1.8 g. of a viscous oilhaving a boiling point of 9697 C./0.5 mm. Hg and consisting of 96% of1-phenylbutene-3-ol according to analysis by gas chromatography. Yield,82% of the theoretical.

EXAMPLE 13 A suspension of 11 g.=40 mmoles of (COD) Ni in 100 ml. ofbenzene is prepared and reacted with 11 g.=80.8 mmoles of anisicaldehyde. Thereafter, about 6 g.=11() mmoles of butadiene areintroduced. After 24 hours, a brown precipitate is formed and, afterremoval of the solvent, reacted with 100 ml. of alcohol (5% of water).After 24 hours, the green suspension is freed from the solvents at 10*mm. Hg. The residue is extracted with ether and the extract evaporatedto give 9.8 g.=29.8 mmoles of 1,6 bis(4 methoxyphenyl)-hexene-(3 )-diol-(1,6)=74% of the theory. Melting point, 140141 C. afterrecrystallization from benzene and petroleum ether.

C H O Calculated, 73.14% C; 7.36% H. Found, 73.00% C; 7.20% H.

EXAMPLE 14 A solution is prepared from 49.5 mmoles of C H .Ni (I) andbutadiene in 200 ml. of ether and mixed at 20 C. with g.=l4l mmoles ofbenzaldehyde. A light 8 brown voluminous precipitate separatesimmediately. After 12 hours, 4.8 g.=14.7 mmoles:29.6% of the theory ofthe sparingly soluble compound (III) are isolated.

C H Ni: Calculated, 17.9% Ni; found, 18.5% Ni.

A suspension of 2.5 g.=7.6 mmoles of III in 30 ml. of benzene isprepared. When adding 15 ml. of glacial acetic acid, a deep red solutionis formed which, after addition of about 0.1 g. of PtO is subjected tocatalytic hydrogenation at 50 atm. The product is processed after 24hours. At 10" mm. Hg and 135145 C., 1.4 g. of 1- phenyltridecanol(l)distil as a viscous oil. Yield, 67% of the theoretical.

EXAMPLE 15 Preparation of 1,6-di(p-dimethylaminophenyl)-trans-3-hexene-1,6-diol 4.6 Grams= mmoles of butadiene are introducedinto a suspension of 10 g.=36.4 mmoles of bis(cyclooctadiene) nickel andthen 10.8 g.=72.8 mmoles of p-dimethylaminobenzaldehyde are added. Themixture is stirred for 16 hours at 20 C. Then the precipitated nickelalcoholate is separated by filtration, washed and the diol liberatedwith the corresponding amount of acetyl acetone. Nickel acetyl acetonateis removed by filtration and the yellow other solution decolorized withanimal charcoal to give 5.8 g. of a crystalline raw product and, afterrecrystallization from ether, 5 g. of the compound C H N O correspondingto 39% of the bis(cyclooctadiene)-nickel charged. Melting point, 122 C.(clec.). The structure is confirmed by IR and NMR spectra.

Preparation of 1,6-di(3-furyl)-trans-3-hexene-1,6-diol .lll ,Hll\O/-CHOH CH; 0114311 on. CHOH \O/ 4 Grams=74.0 mmoles of butadiene areintroduced into a suspension of 10 g.:36.4 mmoles of bis(cyclooctadiene)nickel in 70 ml. of ether. Then 7 g.=72.8 mmoles of furfural are addedat a time and the mixture stirred for 24 hours at 20 C. The nickelalcoholate is formed as a wine-red precipitate which is removed byfiltration and washed with ether. The diol is liberated with thecorresponding amount of acetyl acetone whereby nickel acetyl acetonateis obtained. Processing of the ether solution gives 4.8 g. of rawproduct. Crystallization from benzene gives 4.2 g. of needle-shapedcrystals having a melting point of 108 C., this yield corresponding to46.8%, based on bis(cyclooctadiene)-nickel charged. The structure of thecompound is confirmed by the IR and NMR spectra.

C, H analysis.C H O Calculated, 67.7% C; 6.49% H. Found, 68.2% C; 6.52%H.

The alcohols obtained when hydrolyzing the nickel alcoholates which canbe prepared by the process of this invention and being alpha, omegabifunctional alcohols are useful for the preparation of polyesters withthe particular possibility to cross-link the resultant polyesters bymeans of the double bonds which are still contained in the bifunctionalalcohols. Thus, any of the alcohols mentioned in the examples and in thespecification may be used directly and the nickel alcoholates aspreliminary products for the production of polyesters.

What is claimed is:

1. A process for preparing a novel nickel alcoholate which comprisesreacting a bis-1r-allyl nickel compound with a carbonyl compoundselected from the group consisting of formaldehyde, acetaldehyde,propionaldehyde, butyric aldehyde, acrolein, crotonaldehyde, hexadienal,propargyl aldehyde, benzaldehyde, cinnamic aldehyde, phenylpentadienal,vitamin A aldehyde, anisic aldehyde, vanillin, acetone, methyl ethylketone, mesityl oxide, cyclopentanone, cyclohexanone, acetophenone,benzophenone, fi-ionone, glyoxal, malonic dialdehyde, succinicdialdehyde, diacetyl, acetyl acetone, acetonyl acetone, benzil andbenzoyl acetone.

2. Process according to claim 1, wherein said carbonyl compounds areused as solvents.

3. A process according to Claim 1 wherein said.1r-allyl nickel compoundis blS-(1r-C H Ni.

4. A process according to Claim 1 wherein said bis-1rallyl nickelcompound has the formula 5. 1r-Allyl nickel-1-pheny1butene-(3)-olate. 6.Nickel alcoholate of the formula References Cited UNITED STATES PATENTS5/1968 Heck 260-429 L 1/1969 Wilke 260-429 L 0 DANIEL E. WYMAN, PrimaryExaminer 25 260-347.8, 571, 590, 611 R, 613 R, 6 18 R, 631 R,

635 R, 638 R, 668 R UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patmm.No. 8 4 Datai August a 197# Gunther Wilke and PaulHeimbach Inventor(s) It is certified that error appears in theabove-identified patent land that said Letters Patent are herebycorrected as shown below:

Col 6} line 55 II v H II "0 11 0 should be C H2 O C01. 8, line 44l,6-di(3-furyl)trans should read "l,6-di(g-furyl)-trans.?

Signed and Sealed this twenty-ninth D3) Of July 1975 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN AI P I IIR jfif (ummissilmcr uflatcnrxand Trademarks FORM Po-1osouo-s9) USCQMWDC wwfipu L' 5 GOVERNMENTPRINTING OFFICE:

